[ARM] 5122/1: imx_dma_request_by_prio simpilfication

imx_dma_request_by_prio can return channel number by itself.
No need to supply variable address through parameters.

Also converted all drivers using this function.

Signed-off-by: Paulius Zaleckas <paulius.zaleckas@teltonika.lt>
Acked-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/include/asm-arm/arch-imx/imx-dma.h b/include/asm-arm/arch-imx/imx-dma.h
index 5b1066d..44d89c3 100644
--- a/include/asm-arm/arch-imx/imx-dma.h
+++ b/include/asm-arm/arch-imx/imx-dma.h
@@ -88,7 +88,7 @@
 
 void imx_dma_free(imx_dmach_t dma_ch);
 
-int imx_dma_request_by_prio(imx_dmach_t *pdma_ch, const char *name, imx_dma_prio prio);
+imx_dmach_t imx_dma_request_by_prio(const char *name, imx_dma_prio prio);
 
 
 #endif	/* _ASM_ARCH_IMX_DMA_H */